1. Field of the Invention
The present invention relates to a 3-dimensional (3D) shape measuring apparatus using a shadow moire, and more particularly, to a 3D shape measuring apparatus using a shadow moire, which can measure a 3D shape of a test object by selectively switching on/off a plurality of illuminating parts irrespective of a shape of the test object.
2. Description of the Related Art
A 3D shape measuring apparatus using a conventional moire will be described with reference to FIG. 1.
As shown in FIG. 1, the 3D shape measuring apparatus using the conventional moire includes a control part 10, a work stage 20, a projection part 30, a rotation part 40, and an image sensor 50. The control part 10 controls the 3D shape measuring apparatus, and thereby measures a 3D shape of a test object 21 by using a reflected image which is captured by the image sensor 50. In this instance, the test object 21 is moved to a measuring location to measure the 3D shape of the test object 21. The work stage 20 includes a fixing device 22 and a motor 23 to drive the test object 21 placed on the fixing device 22. When the test object 21 is moved to the measuring location, the projection part 30, the rotation part 40, and the image sensor 50 are provided above the fixing device 22 so as to measure the 3D shape.
The projection part 30 includes a light source 31, a projection grating 32, a grating moving part 32a, a projection lens 33, and a filter 34. The light generated from the light source 31 is projected via the projection grating 32, the projection lens 33, and the filter 34. The light in a form of a grating pattern is directed towards one surface of measuring object 21. To take a reflected image formed when the light in the form of the grating pattern is directed towards the test object 21, the image sensor 50 includes a lens 51 and a camera 52. When the reflected image of the grating-pattern light, which is directed towards one surface of the test object 21, is captured by the image sensor 50, the projection part 30 is rotated into another surface of the test object 21 along an arrow direction, so that the image sensor 50 may capture an image of another surface of the test object 21. The rotation part 40 is placed under the projection part 30 to rotate the projection part 30.
The rotation part 40 includes a support member 41 and a rotation member 42. A first hole 41 a is formed in the support member 41 and thereby enables a grating pattern generated from the projection part 30 to be directed towards the test object 21. A second hole 42a is formed in another side of the rotation member 42 so that the reflected image of the test object 21 may pass through the second hole 42a to a location of the image sensor.
Also, there is another problem in that the 3D shape measuring apparatus using the conventional moire requires a grating moving part to move gratings to each projection part according to the number of projections.
Also, there is another problem that the 3D shape measuring apparatus using the conventional moire requires a grating moving part to move gratings to each projection part according to a number of projections parts by providing the grating to each projection part.